KR102450578B1 - Device and method for initializing channel in nonvolatile memory device - Google Patents

Abstract

The present invention relates to an apparatus and method for initializing a channel of a nonvolatile memory device, and the method for initializing a channel of a nonvolatile memory device according to an embodiment of the present invention includes a plurality of word lines and a plurality of string lines in one block. A method for initializing a channel of a nonvolatile memory device comprising: a first step of applying a voltage to a plurality of string lines included in the block; a second step of switching a bit line passing through the block to a floating state; and a third step of releasing the floating state of the bit line.

Description

DEVICE AND METHOD FOR INITIALIZING CHANNEL IN NONVOLATILE MEMORY DEVICE

The present invention relates to an apparatus and method for initializing a channel of a memory device, and more particularly, to a channel initialization for a nonvolatile memory device capable of reducing power consumption by controlling a bit line when initializing a selected and unselected string line in a read or write verification operation. It relates to an apparatus and method.

A NAND flash memory is a type of nonvolatile memory that retains data even when power is cut off, and inputs and outputs information in an electrical manner. A 3D NAND flash memory in which the internal structure of the NAND flash memory is developed from a two-dimensional planar structure to a three-dimensional vertical structure has been developed and used. Such 3D NAND flash memory shows significantly improved performance in terms of storage space density, speed, durability, and power consumption compared to a planar structure.

In such a nonvolatile memory device, unnecessary power may be consumed due to the effect of parasitic capacitors present in the word line during initialization of the selected and unselected string lines when a read or write verification operation is performed.

US Patent Publication No. 2012-0320678 (published on December 20, 2012)

One of the technical problems to be achieved by the technical idea of the present invention is to provide an apparatus and method for initializing a channel of a nonvolatile memory device capable of reducing power consumption by controlling a bit line when initializing a selected and unselected string line in a read or write verification operation. is in providing.

The method for initializing a channel of a non-volatile memory device according to an exemplary embodiment includes a method for initializing a channel of a non-volatile memory device including a plurality of word lines and a plurality of string lines in one block, wherein the plurality of blocks included in the block are included. a first step of applying a voltage to a string line of a second step of switching a bit line passing through the block to a floating state; and a third step of releasing the floating state of the bit line.

A channel initialization method of a nonvolatile memory device according to another exemplary embodiment includes a channel initialization method of a nonvolatile memory device including a plurality of word lines and a plurality of string lines in one block, the method comprising: transitioning the bit line to a floating state; applying a voltage to a plurality of string lines included in the block; and releasing the floating state of the bit line.

According to an exemplary embodiment, the apparatus for initializing a channel of a nonvolatile memory device includes a plurality of word lines and a plurality of string lines in one block. a string line voltage applying unit for applying a voltage to the string line of the ; a bit line floating switching unit that converts a bit line passing through the block to a floating state; and a bit line floating release unit configured to release the floating state of the bit line.

According to the apparatus and method for initializing a channel of a nonvolatile memory device according to the present invention, power consumption can be reduced by controlling a bit line when initializing a selected and unselected string line in a read or write verification operation.

1 is a schematic diagram for explaining a case where all string lines in a block are turned on to initialize channels of selected/unselected strings with voltages applied from bit lines.
FIG. 2 is a graph illustrating a change in voltage appearing in each element in a block during the same operation as in FIG. 1 .
3 is a schematic diagram for explaining a case of initialization by turning off an unselected string line in a block.
4 is a schematic diagram for explaining a soft erase phenomenon that may occur during the operation as in FIG. 3 .
5 is a flowchart illustrating a channel initialization method of a nonvolatile memory device according to an embodiment of the present invention.
6 is a flowchart illustrating a channel initialization method of a nonvolatile memory device according to another embodiment of the present invention.
7 is a graph illustrating a change in voltage appearing in each element in a block during an operation according to a channel initialization method of a nonvolatile memory device according to an embodiment of the present invention.
8 is a graph illustrating a change in voltage appearing in each element in a block during an operation according to a channel initialization method of a nonvolatile memory device according to another exemplary embodiment of the present invention.
9 is a graph for explaining an operation before entering a floating state in a channel initialization method of a nonvolatile memory device according to another embodiment of the present invention.
10 is a graph for explaining an operation of controlling a time point of transition to a floating state in a channel initialization method of a nonvolatile memory device according to another embodiment of the present invention.
11 and 12 are graphs for explaining an operation of controlling the timing of switching to the floating state and the timing of releasing the floating state in the channel initialization method of the nonvolatile memory device according to another embodiment of the present invention.
13 is a flowchart illustrating a channel initialization method of a nonvolatile memory device according to another embodiment of the present invention.
14 is a block diagram illustrating a channel initialization device of a nonvolatile memory device according to an embodiment of the present invention.

The details of other embodiments are included in the detailed description and drawings.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

1 is a schematic diagram for explaining a case where all string lines in a block are turned on to initialize the channels of a selected/unselected string with a voltage applied from a bit line, and FIG. 2 is an operation similar to FIG. It is a graph showing the change in voltage that appears. Also, FIG. 3 is a schematic diagram for explaining a case of initialization by turning off an unselected string line in a block, and FIG. 4 is a schematic diagram for explaining a soft erase phenomenon that may occur during the operation as in FIG. 3 .

When a read and/or write verification operation is entered in a 3D NAND flash memory structure in which each sub-block can be selected with a multiple selection string line SSL, each string is initialized. However, in this case, unnecessary power may be consumed due to capacitor components existing on the word line of the semiconductor memory.

For example, as shown in FIGS. 1 and 2 , all string lines existing in the block are turned on and channels of the selected string and the unselected string are initialized with a voltage applied from the bit line. In the case of applying a method of simultaneously applying a voltage to the word line, the voltage difference between the initialized channel and the word line increases, thereby increasing the amount of charge consumed to fill the capacitor components existing in the word line.

If this is understood through the graph, 0V is applied to the bit line BL as shown in the second graph of FIG. 2 in a state in which all string lines shown in FIG. 1 are turned on, and 0V is applied to the bit line BL as shown in the first graph of FIG. As shown, when a voltage is also applied to the word line WL and set up, a potential difference between the word line WL, which may have a relatively high voltage value, and the bit line BL, to which 0V is applied, is large. In the case of initialization in this way, a situation arises in which charges must be filled in capacitor components existing across all string lines, and power consumption is inevitably increased.

On the other hand, in order to reduce the amount of consumed electric charge, the bit line BL and the channel of the unselected string lines are connected to each other by turning the unselected string lines A into a turn-off state as shown in FIG. 3 . In the case of applying the method of preventing . For example, as shown in FIG. 4 , in a situation where a negative voltage is applied to the selected word line WL3, a deterioration phenomenon of soft erase may occur due to a potential difference with the boosting channel.

Accordingly, the present invention can solve the problem of power consumption that the initialization method illustrated in FIGS. 1 and 2 may have, and the problem of deterioration that the initialization method illustrated in FIGS. 3 and 4 may have. A method for channel initialization of a non-volatile memory device that does not generate

5 is a flowchart illustrating a channel initialization method of a nonvolatile memory device according to an embodiment of the present invention, and FIG. 6 is a flowchart illustrating a channel initialization method of a nonvolatile memory device according to another embodiment of the present invention. 7 is a graph illustrating a change in voltage appearing in each element in a block during an operation according to the channel initialization method of the nonvolatile memory device according to an embodiment of the present invention. 13 is a flowchart illustrating a channel initialization method of a nonvolatile memory device according to still another exemplary embodiment of the present invention.

As shown in FIG. 5 , in a method for channel initialization of a nonvolatile memory device including a plurality of word lines and a plurality of string lines in one block according to an embodiment of the present invention, a plurality of strings included in a block It may include applying a voltage to the line ( S100 ), converting the bit line passing through the block to a floating state ( S200 ), and releasing the floating state of the bit line ( S300 ).

Also, as shown in FIG. 6 , in the method for initializing a channel of a nonvolatile memory device according to an embodiment of the present invention, the step of releasing the floating state of the bit line ( S300 ) is an unselected string line among a plurality of string lines. It may be performed after the point in time at which the voltage applied to is started to be removed (S250). In addition, according to another embodiment of the present invention, the step of releasing the floating state of the bit line ( S300 ) may be completed before the point in time when a voltage required for sensing is applied to the bit line ( S350 ).

In the channel initialization method of a nonvolatile memory device according to embodiments of the present invention, by floating the bit line BL in a turn-on period of a plurality or all of the string lines included in the block, the bit line ( Unlike the method of initializing the channel by applying 0V or any other voltage to BL), the voltage difference between the word line and the channel is reduced to reduce the amount of charge filling the capacitance components existing in the word line. More specifically, in the period in which the selected and unselected string lines are turned on to initialize the channel of the nonvolatile memory device, the transistor disposed between the bit line BL and the bit line driver is turned off to turn off the bit line ( BL) is plotted. This prevents the voltage applied from the bit line BL from affecting the channel, thereby minimizing the capacitance of the channel seen from the word line WL.

Referring to the first graph of FIG. 7 , the selected string line (Sel. SSL) and the unselected string line (Unsel. SSL) are turned on and for a certain period of time when the voltage is increased, in the graph shown in the second graph of FIG. It can be seen that the bit line BL maintains the floating state for a certain period of time. This is a method of applying a fixed voltage value (eg, 0V) to the bit line BL while the selected string line Sel. SSL and the unselected string line Unsel. SSL are turned on and the voltage is increased in FIG. 2 . different from the method

When a fixed voltage value is applied to the bit line BL while the voltage is increased by turning on all string lines, the voltage of the unselected word line Unsel WL is increased as shown in the third graph of FIG. 2 . While the voltage applied to the unselected string lines is maintained at 0V during the initial predetermined period of have.

On the other hand, when the selected string line and the unselected string line are turned on and the transistor connecting the bit line BL and the bit line driver is turned off for a certain period of time when the voltage is increased, the bit line is placed in a floating state, As shown in the curve C of the th graph, the voltage applied to the unselected string lines may slightly increase (for example, about 0.5V), and accordingly, the voltage difference between the word line and the channel is reduced to reduce the capacitance component present in the word line. It is possible to reduce the amount of charge filling them.

If the method described in FIGS. 3 and 4 is applied, as the channel of each unselected string line is excessively boosted under the influence of the set word line voltage, the voltage applied to any one or more of the unselected string lines is For example, as shown in curve B of the third graph of FIG. 7 , the unselected cell may be boosted to a high enough value (eg, about 3V) to be programmed to an unintended value.

Accordingly, the present invention turns on a plurality of string lines included in a block and maintains a floating state in which a specific voltage is not applied to the bit line BL for a properly controlled period of time, thereby reducing power consumption and soft erase at the same time. It also prevents the occurrence of deterioration phenomena such as

On the other hand, the starting point of the 'predetermined period' for putting the bit line in the floating state may not only be after the point in time when voltage is applied to the plurality of string lines included in the block, but may also be before the point in time when voltage is applied to the plurality of string lines. have.

The technical significance of setting the bit line transition time to the floating state after the voltage application time to the plurality of string lines is to prevent excessive floating by appropriately controlling the floating period. However, even when the timing of transitioning the bit line to the floating state slightly precedes the timing of applying a voltage to the plurality of string lines, the possibility of excessive floating may be small. Accordingly, as shown in the first and second diagrams of FIG. 7 , the starting point of the 'a period of time' for placing the bit line in the floating state may be set somewhat earlier than the timing of applying a voltage to the plurality of string lines.

Accordingly, the execution sequence of the step of applying a voltage to the plurality of string lines included in the block shown in FIG. 5 ( S100 ) and the step of converting the bit line passing through the block to a floating state ( S200 ) is as shown in FIG. 13 . As shown, the step of converting the bit line passing through the block to the floating state ( S600 ) and the step of applying a voltage to a plurality of string lines included in the block ( S700 ) may be performed interchangeably.

However, the timing of releasing the floating state of the bit line is performed after the timing of starting to remove the voltage applied to the unselected string line among the plurality of string lines. Referring to FIG. 7 , it will be confirmed that the floating state is released after the time when the voltage applied to the unselected string line (Unsel. SSL) starts to drop, that is, the time when the unselected string line is turned off. can In addition, the release of the floating state must be completed before the point in time when a voltage required for sensing is applied to the bit line. Meanwhile, the floating state may be released by switching the off state of the transistor disposed between the bit line BL and the bit line driver to the on state.

8 is a graph illustrating a change in voltage appearing in each element in a block during an operation according to a channel initialization method of a nonvolatile memory device according to another exemplary embodiment of the present invention.

In the embodiment proposed in FIG. 7 , the bit line is left in the floating state for a certain period of time when the voltage is increased as the selected string line and the unselected string line are turned on. However, according to another embodiment of the present invention proposed in FIG. In a state in which the bit line is not placed in a floating state, an intended DC voltage may be applied to the bit line using a transistor for a predetermined period when the selected string line and the unselected string line are turned on and the voltage is increased. For example, the drain terminal of the PMOS transistor is connected to the bit line, and an input signal applied to the gate terminal is turned ON/OFF while an appropriate DC voltage is applied to the source terminal according to the voltage value between 0 and VDD to be supplied to the drain terminal. By controlling OFF, as shown in FIG. 8 , it is possible to control the voltage applied to the bit line for a certain period to have a constant DC voltage value.

9 is a graph for explaining an operation before a floating state in a channel initialization method of a nonvolatile memory device according to another embodiment of the present invention, and FIG. 10 is a nonvolatile memory device according to another embodiment of the present invention. It is a graph for explaining the operation of controlling the time point of transition to the floating state in the channel initialization method of the memory device, and FIGS. 11 and 12 are the floating state in the channel initialization method of the nonvolatile memory device according to another embodiment of the present invention. It is a graph for explaining the operation of controlling the timing of switching to the state and the timing of releasing the floating state.

In the method for initializing a channel of a nonvolatile memory device according to an embodiment of the present invention, prior to the step of switching the bit line to a floating state ( S200 ), a constant voltage of 0V to a driving voltage (VDD) or less is applied to the bit line. Step S50 may be further included. 7 shows an embodiment in which the selected string line and the unselected string line are turned on to put the bit line in a floating state for a predetermined period of time when the voltage is increased. In FIG. 8, the bit line has an intended DC voltage value for the predetermined period. 9 shows an embodiment in which a part of the predetermined period has the intended DC voltage and the remaining period is made in a floating state.

Meanwhile, as shown in FIG. 6 , as well as the step S50 of applying a constant voltage from 0V to the driving voltage VDD or less to the bit line, before the step S100 of applying the voltage to the plurality of string lines. may be Although not shown in the embodiment shown in FIG. 13 , the step (S50) of applying a constant voltage of 0V to the driving voltage (VDD) or less to the bit line precedes the step (S600) of converting the bit line to a floating state. can be performed.

In FIG. 9 , unlike in FIG. 7 , the timing of switching the bit line to the floating state is set after the timing of applying voltages to the plurality of string lines. In addition, a state in which a constant voltage of 0V to a driving voltage VDD or less is applied to the bit line before the transition to the floating state is illustrated. Here, the constant voltage may be preset as needed. If a constant voltage value greater than 0 is applied to the bit line before switching the bit line to the floating state, it is expected to reduce the amount of charge consumed by reducing the voltage difference between the word line and the bit line during the period during which the constant voltage value is applied. can

In addition, in the channel initialization method of the nonvolatile memory device according to another embodiment of the present invention, the timing of switching to the floating state or the timing of releasing the floating state may be set differently according to the address of the word line.

Driving voltages applied to drive a plurality of word lines existing in one block may be different from each other as needed. That is, a voltage applied to a specific word line may be higher or lower than a voltage applied to another word line. Considering that the boosting degree of a string line may be higher for a word line having a relatively high applied voltage compared to a word line not having a relatively high voltage, it is intended to control the transition time and release time of the floating state.

For example, as the voltage value applied to the word line increases, the transition to the floating state may be delayed as shown in curves a, b, c, and d as shown in FIG. 10 . By reducing the floating period as described above, the boosting degree of the string line is controlled.

In addition, the timing of switching to the floating state may be delayed while the timing of releasing the floating state may be advanced. As shown in FIG. 11 , the timing of switching to the floating state and the timing of releasing the floating state may be controlled together as shown in curves a, b, c, and d. Although not shown in the drawings, an embodiment in which the floating period is controlled by fixing only the timing of switching to the floating state and controlling only the timing of releasing the floating state is also within the scope of the present invention.

According to another embodiment of the present invention, in a channel initialization method of a non-volatile memory device in which a plurality of bit lines passing through one block exist, the plurality of bit lines are applied to the plurality of bit lines according to the direction in which a voltage is applied to the word line. The floating period can be controlled differently for each other.

The point at which voltage is applied to the block may be specified. For example, assuming that a plurality of bit lines BL0, BL1, BL2, BL3, ?? BLn sequentially exist in one block and a voltage is applied to a word line near a point where BL0 is located, the voltage As the bit line is closer to the point to which this is applied, the timing of switching to the floating state may be delayed or the timing of releasing the floating state may be advanced. This is also to properly control the degree to which the string line is boosted.

According to another embodiment of the present invention, in the method for initializing a channel of a nonvolatile memory device including a plurality of blocks, the timing of switching to the floating state or the timing of releasing the floating state may be set differently depending on the address of the block. have.

When a voltage is applied to a plurality of blocks included in the nonvolatile memory device, a time delay may occur due to a resistive component in the memory device, and thus the timing at which the voltage starts to be formed may be different for each block. Accordingly, in consideration of such a temporal delay, the floating timing of the bit line is also differently controlled according to the address of the block as shown in FIG. 12 . For example, as a block is further away from a point to which a voltage is applied, at least one of a time point for switching to a floating state or a time point for releasing the floating state is controlled as shown in curves a, b, c, and d in FIG. 12 .

14 is a block diagram illustrating a channel initialization device of a nonvolatile memory device according to an embodiment of the present invention.

According to an embodiment of the present invention, the channel initialization device 10 of a nonvolatile memory device including a plurality of word lines and a plurality of string lines in one block includes the string line voltage applying unit 100 and the bit line floating It may include a switching unit 200 and a bit line floating release unit 300 .

The string line voltage applying unit 100 applies voltages to a plurality of string lines included in the block.

The bit line floating switching unit 200 converts a bit line passing through a block to a floating state. In particular, the bit line floating switching unit 200 may apply a predetermined voltage equal to or greater than 0 driving voltage or less to the bit line before the bit line becomes a floating state.

The bit line floating release unit 300 releases the floating state of the bit line. In particular, the bit line floating release unit 300 determines the floating state of the bit line after the point at which the voltage applied to the unselected string line among the plurality of string lines starts to be removed and before the point at which the voltage required for sensing is applied to the bit line. can be turned off

The timing at which the bit line floating switching unit 200 switches to the floating state or the bit line floating canceling unit 300 releases the floating state of the bit line may be set differently depending on the address of the word line. Specifically, as the voltage value applied to the word line increases, the bit line floating switching unit 200 delays the transition to the floating state, or the bit line floating canceling unit 300 advances the timing of releasing the floating state. can

In a situation in which a plurality of bit lines pass through the block, the timing at which the bit line floating switching unit 200 switches to the floating state or the bit line floating canceling unit 300 releases the floating state of the bit lines is a word line. It may be set differently for each bit line according to a direction in which a voltage is applied. Specifically, as the bit line is closer to the point to which the voltage is applied, the bit line floating switching unit 200 delays the transition to the floating state, or the bit line floating canceling unit 300 releases the floating state. can be advanced

In a situation in which a plurality of blocks exist in the nonvolatile memory device and the bit line passes through the plurality of blocks, the bit line floating switching unit 200 switches to the floating state or the bit line floating canceling unit 300 is The timing of releasing the floating state of the bit line may be set differently according to the address of the block. Specifically, as the distance from the point to which the voltage is applied increases, the time of switching to the floating state may be delayed, or both the timing of switching to the floating state and the timing of releasing the floating state may be delayed.

The function performed by the string line voltage application unit 100 is to apply voltages to a plurality of string lines included in a block in the channel initialization method of the nonvolatile memory device (step S100 of FIG. 2 ; step S700 of FIG. 13 ). ) corresponds to In addition, the functions performed by the bit line floating switching unit 200 include converting a bit line passing through a block to a floating state (step S200 of FIG. 2 ; step of FIG. 13 ) in the channel initialization method of the nonvolatile memory device described above. S600) and the functions performed by the bit line floating release unit 300 include the step of releasing the floating state of the bit line (step S300 of FIG. 2; step of FIG. 13) in the channel initialization method of the nonvolatile memory device. S800).

Accordingly, a detailed description of the channel initialization device 10 of the nonvolatile memory device can be understood with reference to the detailed description of the channel initialization method of the nonvolatile memory device and corresponding drawings, and thus repeated description will be omitted. .

On the other hand, the term '~ part' used in this embodiment, that is, '~ module' or '~ table', etc. means software, hardware such as FPGA (Field Programmable Gate Array) or Application Specific Integrated Circuit (ASIC). It means a component, and a module performs certain functions. However, a module is not meant to be limited to software or hardware. A module may be configured to reside on an addressable storage medium and may be configured to refresh one or more processors. Thus, as an example, a module includes components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, procedures, subroutines. files, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and modules may be combined into a smaller number of components and modules or further divided into additional components and modules. In addition, components and modules may be implemented to regenerate one or more CPUs in a device.

Those of ordinary skill in the art to which the present invention pertains will understand that the present invention may be embodied in other specific forms without changing the technical spirit or essential features thereof. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims described below rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention. should be interpreted

100: string line voltage applying unit
200: bit line floating switching unit
300: bit line floating release unit

Claims (10)

A method for channel initialization of a nonvolatile memory device including a plurality of word lines and a plurality of string lines in one block, the method comprising:
applying a voltage to a plurality of string lines included in the block;
transitioning a bit line passing through the block to a floating state; and
releasing the floating state of the bit line;
How to initialize a channel in a non-volatile memory device.
According to claim 1,
The step of releasing the floating state of the bit line comprises:
It is performed after a point in time when the voltage applied to the unselected string line among the plurality of string lines starts to be removed,
Completed before the point in time when the voltage required for sensing is applied to the bit line,
How to initialize a channel in a non-volatile memory device.
According to claim 1,
Converting a bit line passing through the block to a floating state comprises:
In a state in which the bit line is not placed in a floating state, it is switched to a state in which a constant voltage equal to or greater than 0 and equal to or less than a driving voltage is applied,
How to initialize a channel in a non-volatile memory device.
According to claim 1,
In the step of converting the bit line passing through the block to a floating state,
Before the bit line enters a floating state, a constant voltage equal to or greater than 0 and equal to or less than a driving voltage is applied to the bit line.
How to initialize a channel in a non-volatile memory device.
According to claim 1,
The timing of switching to the floating state or the timing of releasing the floating state is set differently according to the address of the word line,
As the voltage value applied to the word line increases, the timing of switching to the floating state is delayed or the timing of releasing the floating state is advanced.
How to initialize a channel in a non-volatile memory device.
According to claim 1,
The timing of switching the bit line to the floating state or the timing of releasing the floating state is set differently for each bit line according to a direction in which a voltage is applied to the word line,
There is a plurality of bit lines passing through the block,
The closer the bit line is to the point where the voltage is applied, the more delaying the time of transition to the floating state or the earlier of the time of releasing the floating state.
How to initialize a channel in a non-volatile memory device.
According to claim 1,
The non-volatile memory device includes a plurality of blocks, and the bit line passes through the plurality of blocks,
The time to switch to the floating state or the time to release the floating state is set differently depending on the address of the block,
The further the block is from the point where the voltage is applied, the longer the time of transition to the floating state is delayed.
How to initialize a channel in a non-volatile memory device.
According to claim 1,
The transition to the floating state is effected by turning off a transistor disposed between a bit line driver and a bit line passing through the block.
How to initialize a channel in a non-volatile memory device.
A method for channel initialization of a nonvolatile memory device including a plurality of word lines and a plurality of string lines in one block, the method comprising:
transitioning a bit line passing through the block to a floating state;
applying a voltage to a plurality of string lines included in the block; and
releasing the floating state of the bit line;
How to initialize a channel in a non-volatile memory device.
A channel initialization device for a nonvolatile memory device including a plurality of word lines and a plurality of string lines in one block, the device comprising:
a string line voltage applying unit applying voltages to a plurality of string lines included in the block;
a bit line floating switching unit that converts a bit line passing through the block to a floating state; and
and a bit line floating release unit for releasing the floating state of the bit line;
A channel initiator for non-volatile memory devices.

Images